The present invention is in the field of housings for establishing and securing the connection between a light-transmitting optical fiber and a fiber optic transmission (FOT) device.
Fiber optic transmission (FOT) devices, also called optical-electronic devices, optoelectronic devices, optical converters and other names known in the art, are coupled with optical fibers for data and signal transmission by converting optical signals into electrical signals, electrical signals into optical signals, or both. Various connector and housing arrangements are known, many with the object of improving the efficiency of the coupling or connection by providing a uniform gap between the optical fiber and a light-receiving or light-transmitting interface on the FOT. This gap is preferably kept as small as possible to maintain good signal quality. However, the typical plastic connector housing which surrounds, aligns and establishes the optical-electronic coupling between the optical fiber and the FOT tends to introduce inconsistency into the spacing of the FOT and optical fiber due to tolerance-induced xe2x80x9cfloatxe2x80x9d in the molded plastic FOT cavity.
An additional difficulty in establishing uniform spacing between the FOT and optical fiber is the need for electromagnetic interference (EMI) shielding for the FOT in the housing.
The present invention is a device for simultaneously shielding and properly tolerancing an FOT relative to an optical fiber coupled thereto by a connector housing. In its broadest form, the invention comprises a metal EMI casing surrounding the FOT body (with an opening for the optical fiber interface), the EMI casing having at least one spring member acting against the connector housing to bias the FOT interface toward the mating optical fiber. This establishes and maintains uniform spacing between them, thereby overcoming excessive xe2x80x9cfloatxe2x80x9d and spacing caused by variations in the coupling, connector or housing structure.
In one preferred form of the invention, the spring member is part of the EMI casing itself and comprises one or more raised, flexible bumps or strips of the metal casing material located on a side (the xe2x80x9cupperxe2x80x9d side) opposite the FOT interface to force the FOT interface toward the coupled optical fiber in the connector housing. Alternately, the EMI casing may contain such spring members at different locations to act against different portions of the connector housing and further align and tolerance the FOT interface relative to the optical fiber. The lower wall of the metal EMI casing around the interface opening can be closely toleranced to establish the preferred spacing of the FOT interface from the optical fiber.
In a further alternate embodiment, the spring member is a resilient, gasket-type member on the FOT or pre-installed in the FOT receptacle in the connector housing to receive the FOT under compression, again biasing the FOT interface against the optical fiber.
These and other features and advantages of the invention will become apparent upon a further reading of the specification, in light of the accompanying drawings.